Art of hardening metal



UNITED. STAT-TIES,

HAROLD A. LOMAX, or rrrrsnunen, rEn'NsYnvaura.

ART OF. HA RDENING- METAL.

Specification of Letters Patent.

Patented A r. 12, 192 1.

Application filed October 10, 1919. Serial No. 329,700.

To all 10 ham it may concern:

Be it known that I, HAROLD A. LOMAX, 'a citizen of the United States,residing at Pittsburgh, in the county of Allegheny and State ofPennsylvania, have invented certain new and useful Improvements in theArt of Hardening Metal, of which the following is a specification.

My invention consists of an improvement in the art ofhardeningsegregated portions or areas of cast metal by the incorporationtherewith of a controlling alloy. As is well known, the combination witha base metal, as iron or steel, of a suitable alloy or alloys producesresults as to hardness, tensile strength, or otherwise within wideranges, 1

depending on the kind and quantity of the alloys used. In themanufacture of rolls, dies, plates, anvils, etc., it is desirable toprovide a very hard surface coating at one or more sides with acomparatively soft interior body and such result is commonly effected bythe use of alloy 01' alloys mixed with the entire'batch or charge fromwhich the casting is made, either with or without the well known chilltreatment in the easting operation, or by accompanying heat treatment,or other means.

My invention has in view to greatly reduce the proportionate quantity ofrelatively expensiv alloy or alloys compositions or compounds byapplying the same to the surface or surfaces only, and to limiteddepths, by fusion therewith of limited quantities, so supported orlocated within the mold, either sand or chill, that the alloy will beincorporated with the selected surface portions of the casting in theformative operation, and will be fixedly combined therewith in theresulting casting.

In carrying out my invention I utilize any suitable supportingframework, as wires, rods, networks, expanded metal, or the like, withwhich the alloy is associated, so ar ranged within the mold at its outerportions that the molten metal will absorb and fuse the alloy and itssupporting framework and embody it at such portions in the exterior orworking portions of the casting, the main interior body portionremaining unaffected.

In the drawings, which are merely typical embodiments of the inventionas applied for instance to a roll,

Figure 1 is a vertical sectional view of a roll casting mold utilizingmy invention, as applied to a straight faced roll; 1

Fig. 2 is apartial similar view showing the invention as used with abeam roll; and

Figs. 3 and 4 are detail views showing portions'of one. available formof the alloysupporting framework with the alloy carried thereby.

The castingmold 2 of sandis formed within the flask 3 in theusual wayproviding the interior casting cavity 4: and any supplemental portionsthereof, to which th molten metal is supplied by-the usual conduit, asis commonly practised in this art. Within the mold cavity and adjacentto the outer portions thereof, or wherever it is desired to combine thealloy with the casting, I arrange and suitably support'the alloycarrying framework 6.' This may be of various suitable material, as wirenetting,

rods, 01- the like, and in or upon this frame work the alloy or compoundis carried, as indicated at 7, Figs. 3 and 4. l

The alloy isjpreferably in comminuted, powdered, or fragmentary form,and mixed with any suitable neutral binder, as molasses, or the like,whereby it maybe held together and attached to the frame 6. The frame,so charged with the alloy or com pound is then arranged within the moldcar ity around and adjacent its inner walls so that the molten metalwill absorb and fuse both the frame and alloy, dissolving the elements,and combining them at the same relativelocations only. If preferred, the

framework may be composed of a metal in which is incorporated a suitablealloy, so that the metallic frame itself will impart the desired effectto the casting, when melted. By this operation, the casting will becomehardened or otherwise affected, dependent on the alloy used, .at suchportions only, leaving those portions as the interior, which are remotefrom the alloy zone, unaffected.-

It will, of course, be understood that two or more layers of theframework may be utilized or the quantity and depth of the alloy may begraduated to suit the objects.

in View by the skilled metallurgist or foundryman. Also, that it may beapplied v and embodied .in the resulting casting in any manner desired,depending on the ex-v pected results, as to "the controlled surfaces orportions. The advantages of the invention reside in the ease of control,economy of alloy, and the facility of treatment of a wide diversity ofshapes or designs'of castings.

1 ing a mold, locating and supporting an al-- What I claim is: i

1. The process of casting metals consisting in supporting a portion ofalloy within a mold at predetermined locations thereof and fusing thsame with the molded metal of the casting. 2. In metal casting, theprocess of formloy within the mold, and then filling the cavity of themold with molten metal and amalgamating the alloy with the metal in theresulting casting at portionsoccupied by the alloy Within the mold.

3. In metal casting, the process of forminga mold, locating a supportingframework embodying an alloy within the mold at predetermined locationswith reference to its embodiment in a resulting casting, and

- then filling the cavity of the mold with molten metal and amalgamatingthe framework and alloy with the metal in the resulting casting atportions approximating the original location of the alloy.. 7

In testimony whereof I hereunto aflix my signature.

'- HAROLD A. LOMAX.

